The overall objectives of the Johns Hopkins Postdoctoral Training Program in Medical Genetics are to recruit and educate physician-scientists who have the potential to become leaders in the field of Genetic Medicine. Our program is designed to expose trainees to all facets of modern medical genetics and genomics extending from the laboratory to the patient setting. Johns Hopkins provides leadership in the categorization and mapping of inherited traits, the application of genomic and computational methods to the identification and understanding of multiple genes and their role in human diseases, and in clinical studies, diagnosis, classification, and treatment of Mendelian disorders and multifactorial disorders with significant genetic contributions. This postdoctoral training experience emphasizes mentored research in genetics and genomics, and prepares trainees for a career in academic medicine. The McKusick-Nathans Institute of Genetic Medicine (IGM) oversees the clinical, educational, and research activities in human genetics of the Johns Hopkins University School of Medicine. To meet the challenges in the rapid development of clinical genomics and the need for integration of genetics into all medicine, the IGM has taken major initiatives to expand genome research and genomic medicine, which include establishing (1) the Center for Computational Biology (2) the Baylor-Hopkins Center for Mendelian Genomics (BHCMG), and (3) the Johns Hopkins Clinical Genomics Center (CGC). These centers were built on the strength of genetics and genomics resources at Hopkins including the Online Medelian Inheritance in Man (OMIM), an encyclopedia of more than 3000 known and unexplained Mendelian disorders established by D r. Victor McKusick in 1960's , and Center for Inherited Disease Research (CIDR), a NIH funded national resource for genetics researchers directed by Dr. David Valle since 1996. The IGM has made a great effort in training, recruiting, and retaining physician-scientists. Currently 28 of 46 (58%) of mentors of this T32 program have MD degree. Since last renewal of this application, the IGM added 9 physician scientists to its faculty, which shows the commitment of IGM leadership and a highly supportive training environment. Together with other faculty, these new physician scientists provide excellent mentorship and great role models for our resident trainees. The IGM clinical genetics-training environment is excellent with particular strength in inborn errors of metabolism, connective tissue disorders, cardiovascular genetics disorders, skeletal dysplasia, epigenetics, neurodevelopmental disorders, and clinical genomics. IGM is the home for OMIM, an encyclopedia of >3000 known and unexplained Mendelian disorders. Johns Hopkins and affiliated training sites have >40 clinics and programs caring for adult and children with individual genetics disorders including Huntington disease clinic, Center for APKD, Center for Inherited Heart Disease, Muscular Dystrophy clinic, Down syndrome clinic, Fragile x syndrome clinic, peroxisomal and mitochondrial disorder clinic, Rett syndrome clinic, and many others. To further expand clinical and research training opportunities for our trainees, we established a training consortium with NHGRI medical genetics residency program in 2012. This allows our trainees to get access to the vast resources and leading investigators in genetics research at NIH including the Undiagnosed Disease Program directed by Dr. William Gahl and ClinSeq, a large scale medical sequencing clinical research program directed by Dr. Leslie Biesecker. Our training program has an outstanding track record of educating physician-scientists who have made and continue to make substantial contributions to medical genetics. Over the last 5 years, the vast majority (86%) of our graduates took positions in academic institutions. Among the training-grant supported trainees (n=5) in the current year, 40% (n=2) are under-representative minority (URM). Our three-year core curriculum for categorical program includes 12 months of concentrated clinical training and 6 months of research-oriented clinical experience. This is followed by 18 months of mentored research training in genetics. Research is performed under the auspices of a carefully selected mentor, with additional mentoring and career guidance provided by the Program Director and senior faculty members. After successfully completion of the program, trainees are eligible for certification by American Board of Medical Genetics in clinical genetics and have a strong research experience to embark on independent career as physician-scientists. In recent year, our program enjoys a rapid growth of combined training programs with pediatrics (4 years), internal medicine (5 years), and maternal fetal medicine (4 years). These combined programs have similar core curriculum in medical genetics and have attracted a much larger pool of outstanding applicants for residency training in medical genetics. Our program currently averages 10 trainees per year and 5 trainee stipends per year are requested in this application. In summary, the rapid advancement in genomic medicine provides a great opportunity and challenges in training of physician-scientists who have the potential to be future leaders in genetic medicine. Our training program, with its excellent training environment and resources, and a group of world-class geneticists who are devoted to excellence in research, education and patient care, is well positioned to lead the efforts and meet these historical challenges.